Refrigerating apparatus



March 3l, 1936. o, M SUMMERS 2,035,575

REFRIGERAT ING APPARATUS Original Filed Nov. 3, 1926 5 Sheets-Sheet l REFRIGERAT ING APPARATUS Original Filed Nov. 3, 1926 3 Sheets-Sheet 2 l om for March 31, 1936. o. M. SUMMERS 2;\J"l""-5,575

RFRGERTNG APPARATUS original Filed Nov. 3. was 5 sheets-Sheet 3y 'W @www Patented Mar. 3.1, 1936 UNITED STATES PATENT OFFICE REFRIGERATIN G APPARATUS 4 Application November 3, 1926, Serial No. 145,950 Renewed November v22, 1934 5 Claims.

The present invention relates to controllers, and particularly to controllers of the pressureresponsive type.

In pressure-responsive controllers it is the usual practice to provide 'the controller with a pressure chamber having a wall adapted to be flexed by the pressure within the chamber, which flexing is utilized to actuate the device to be controlled. When such controller is included in a system in which there is present periodic pulsations in pressure, as, for example, in compressiontype refrigerating systems, the flexible wall, due to said pulsations, continually vibrates and causes same to disintegrate quickly. One of the objects of the present invention is to prolong the life of such flexible wall by preventing the vibration thereof. One manner of carrying out this object is to subject the flexible wall to the mean pressure only within the system.

Another object of the present invention is to provide a controller which will perform a certain function under certain conditions and perform another function under another condition, and to construct and arrange said controller whereby it may be adjusted so that either of the conditions at which the functions take place may be varied independently of the other.

A still further object of the present invention is to combine into a simple, compact structure,

a. controller having means which is responsive normally to certain conditions for performing certain functions, as, for example, opening and closing a, switch, and means which Ais responsive to abnormal conditions for rendering the rst means inoperative to perform certain functions.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings, wherein a preferred form of the present invention is clearly shown.

In the drawings: Y

Fig. 1 is a front view partly in section, of the improved controller;

- 22. Adjacent the lower portion and on opposite sides thereof, there are provided diaphragms 23 and 24 which are spaced from theupright 22 by tends through the upright 22.

gaskets 25 and 26 to provide chambers 21 and 28, respectively, between said diaphragm 23 and upright 22, and between upright 22 and diaphragm 24. Plates 29 and 30 are also disposed on opposite sides of the upright 22 and are arranged co- 5 extensive with the diaphragms 23 and 24. The diaphragms, gaskets and plates are suitably secured to the upright 22 by screws 32. A disc' 33 is disposed Abetween the plate 29 and the .diaphragm 23, and a disc 34 is disposed between the 10 diaphragm 24 and plate 30. Ears 36 are carried by the plate 29, which ears support the fulcrum pin 31 upon which is pivotally mounted a lever 38. One end of lever 38 is arranged to be engaged by the disc 33 and the other end of said lever en- 15 gages a pin 48 which extends through the upright 22. 'Ihe plate 30 carries ears 4l, which .ears support a fulcrum pin 42 which in turn carries an operating member or lever 43. 'Ihe lower end of said lever 43 is arranged to engage with pin 48. 20 A pin 44 pivotally connects lever 43 with ears 45, which ears are secured to the disc 34.

The plate 29 is tapped at 46 to receive a coupling which is connected with a source of pressure, and a passage 41 connects said tapped por- 25 tio-n with the chamber 21, said passage including a drilled hole within the plate 29 and diaphragm 23 and a cut-away portion in the gasket 25. The plate 30 is tapped at 48 and is provided with a passage 49 similar to that of 41, which passage 3o connects with chamber 28. Pressure within the chamber 21 causes the disc 33 to move outwardly androtate the lever 38 in a counterclockwise direction, which will cause the lever 43, by means of the pin 40, to rotate in a counterclockwise 35 direction. Pressure within the chamber 28 will cause the disc 34 to move outwardlyand rotate the lever 43 in a clockwise direction.

Adjacent the upper portion of the upright 22 there is provided a sleeve 50 which extends 40- through said upright and is' suitably secured thereto. A plunger 5I extends through one end of said sleeve and the extreme end thereof is provided with a cone-shaped recess 52. A screwthreaded bushing 53 is connected with the oppo- 45 site end of the sleeve 50-and a spring 54 is located within the sleeve 50 and is disposed between the bushing 53 and a stop 55, and normally tends to force the plunger 5| to the right. Stop 55 engages the end wall of a sleeve 50 and thus 50 limits the movement of said plunger 5|.

A stem 51 is located above the pin 5| and ex- Stem 51 is provided with a stop 58 to limit the movement of said stem toward the left. A nut 59 is provided 55 able within a slot 62 formed'in lever 43. Ears 64 are provided by the upright 22 and extend parallel to the plunger and the stem 51. A fulcrum pin 65 is carried by the ears 64, which in tprn carries an actuating mechanism including parallel-spaced arms 66 which support a roller 61. `A spring 68 is wound about the pin 65 and wise direction.

A switch lever 18 is, bodily or translatively carried by the lever 43, by a pinvll. The lower arm of lever 18 is connected with a link 12 by pin 13, which link is connected to a pivotallymounted contact 14 by a pin 15. Contact 14 is pivotally supported at 18` upon an insulating block 11. 'I'he contact 14 is lprovided with a stop 19 to prevent the countercltickwisel movement of said contact 14 beyond a certain limit. Contact 14 is arranged to engage with contact 88 carriedby the insulating block 11.. The upper end cf -lever is provided with a cam 82 having camming surfaces 83 and 84 either of 'which is arranged to cooperate with the roller 61. When the roller 61 engages the camming surface 84,

; the lever 10 will be in the position shown in Fig.

l, the stop 19 of the pivoted contact 14 limiting the movement of the lever 10. When the lever 43 is mpving outwardly, carrying with it the lever 10, the camming surface 84 will move over the roller 61 and after the apex, formed by the camming surfaces 83 and 84, has moved beyond the roller, the roller 81 will engage the camming surface 83. When this occurs, the spring 68 will force! the roller 61 downwardly, which in turn will quickly rotate the lever 10 in a clockwise direction. when the lever 43 moves in the opposite direction, lever 18 will be moved, so that the camming surface" 83 will be moved beyond the .roller and when said 'roller engages -surface 84 the lever 10wi11 guickly rotate about-pivot 1| in a counterclockwise direction. Fig. l shows the position of lever 43 vwhile said lever is moving toward the right and the lever 10 is still in the Vposition in which the roller 61 maintains contact 14 separated from contact 80. A stillV lfurther l movement 'f the lever 4,3 to the right is necessary before camming surface 83 engages roller 61; Fig. 2 shows the position of lever 43' while said lever ia moving toward. the left, the camming surfaceli'being still in engagementlwith the said miler. It wlll'be noted thatwhen the lever 43 is moving toward the right, the fulcrum pin 1| of lever 18 is farther to the right when the apex o!v cam 8 2 engages roller 61, than when the apex engages roller 81 while the lever 43 is moving toward the left. This is the result of the,V`

lever 'I8 being pivotally and translatively carried' a. projection 85 on the lever 43.which is adapted by the', lever 43 since the lever .10 is at a different angle while said lever 43 is moving in one direction than the 'angle of lever lliwhen lever 43 moves in the opposite direction. 'Ihe movement of the lever 43 to the right is resisted bythe spring 68 and. the-movement of the lever 43 to the left is resisted by the spring 54, there being to engage plunger 5| to-compress the spring 54. The arrangement is such that the stop 55 on the plunger 5| will engage the end wall of sleeve 50 before the lever- 43 has moved to such a pothe lever 43 will move to the left and while the cammingsurface 83 is still engaging the roller 61, the 'stop 58 upon the stem 51 will engage the y upright 22 and thus render the spring ineifective normally tends to rotate said roller 61 in a. clock:

the spring 54 will .resist the movement of the 15 lever 4'3 tojthe left and the tension'of this spring can be adjusted by the nut 53. Since spring 60 is now ineffective, the tension of ,spring 54 alone controls the pressure at which the contacts 14- and 80 are separated. Thus it is apparent from the foregoing description that there is provided high and lpwpres'sure adjustments which are entirely independent of one another, whereby the pressure"at-which the contacts are closed can be adjusted entirely independently of the pressure at which the contacts are opened and, likewise, the pressure at which the contacts are opened can be adjusted vindependently of the pressure ,at which the contacts are closed.

The present invention is particularly adapted to refrigerating systems in which it is desirable `to render a motor operative when a predeterforce the compressed refrigerant through a pipe 96; into a condenser 9|, whence it passes by a pipe 92 to the evaporator 88. The chamber 28 of the .controller 20 is connected by a pipe 93 with the low-pressure pipe .895 When the motor 81 and'compressor 86' are idle, the evaporator becomes warmer and the 'refrigerant Withiny the evaporator 88, pipes 89 andy 93 will increase in pressure and when such pressure attains a predetermined value, contacts 14 will close with contact 80 to complete the electrical circuit to the motor 81. The operation of the compressor 86 will cause the pressure within the low-pressure side of refrigerating system to decrease and when said pressure falls to a predetermined value, which value is computed in accordance with the temperature desired in the evaporator 88, the controller 20 will separate contact 14 from contact 80 totthusrender the motor 81 inoper ative.

In case the refrigerating system does not operate'satisfactorily, as, for example, the refrigerant in the condenser 9| is not cooled as required, the excessive pressureA within the highpressure side of the system will be transmitted to chamber 21l through the pipe 94, which pipe is co ected on the high-.pressure side of the refrig ting system. When an excessivepressureis present within the system, the pressurel I within the chamber 21 will force the diaphragm 70 23 outwardly and rotate the lever 38, which le- -by contact 14 is separated from contact 80.

In systems in which there is present periodic .is vibrated at a relatively high speed 2,085,575 pulsations such as those caused by the opera- I pipes 93 and 94 have a relatively small crossprovide a resistance to the ilow of refrigerant to sectional area and are of such length so as to such an extent that the pulsations are not .transmitted to the chambers 21 and 28. By providing this resistance, the p1 essure values do not change rapidly within said chambers and said chambers are responsive only to the mean pressure within the respective high-pressure and low-pressure sides of the refrigerating system. By subjecting said diaphragms only to the mean pressure within the system, no pulsation is present within said chambers and, therefore, the diaphragms -23 and 24 will not vibrate.

While the form-of embodiment of the invention as herein disclosed, constitutes-a preferred form, it is to be understood that otheriorms might be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows:

l. An automatic switch including a plate, a pair o'f diaphragms located one on either side of the plate, said diaphragms having their edges sealed to the plate,l passages connecting to each of the chambers formed between each of the diaphragms and the plate for extending said diaphragm, a follower for each of the diaphragms, a lever to be actuated and a link mechanism connecting each of the followers with the lever for causing the lever to be actuated by the movement of the diaphragms.

2. An automatic switch including a plate, a pair of diaphragms located one on either side of the plate, said diaphragms having their edges sealed to the plate, passages connecting to each of the chambers formed between each of the diaphra'gms and the' plate for extending said diaphragm, a follower for each of the diaphragms, a lever to be actuated and a link mechanism connecting each of the followerswith the lever for causing the lever to be actuated by the movement of the diaphragms, said lever having a second lever pvotally connected thereto with a cam nose on the one end and a vswitch mechanism connected to theother end. a spring pressed cam roller mounted upon said plate and having its roller in contact with said cam nose, a buifer type spring resistance means for resisting the movement of the lever in one direction and adjusting means for said spring means and a second springmeans having a lost motion connectionwith the lever for resisting the movement of the lever in the opposite direction, said spring means having means for adjusting the same independently'of the buffer type resistance means.

, 3. A pressure operated controller includingv means for controlling the flow of a medium through a circuit, pressure operated means for.

opening and closing said controlling means, snap acting means for controlling' the opening and closingof said last mentioned means, a member connected to the pressure operated means, a plurality of springs adapted to act in opposite directions independently of each other upon the member, means for confining each of said springs so that each one can act upon the member only when'the other springs cannot act upon the member, said member having a lost motion connection with one of the springs.

4. A control device including a pressure operated means, a member connected to and moved by said pressure operated means, a plurality of independent separately conned spring means, said spring means each having means located in the path of movement of and engaged by said member only near the extremities of movement of said member in each direction, one of said spring means being disengaged before the other spring means is engaged by the member during movement in each direction to provide va zone of `movement free of said spring means, means operated by said pressure responsive means for controlling the ow of a medium through a circuit, and snap acting means for causing said last mentioned means to operate withl a snap action.

5.A control device including a member, a plurality of separate pressure responsive means acting independently upon saidmember in opposite directions, a plurality of springs means acting upon said member, means for confining the spring means so that only one can act upon the member at a time, means for independentlyadjusting said spring means, means operated by said member for controlling the flow of a medium, snap acting means for controlling the movement of said member.

OTTO M. SUMMERS. 

